ES2249035T3 - OXIDE ACID PRESENTING MICRO AND MESOPOROUS FEATURES: ITQ-36 - Google Patents

Abstract

The invention deals with a microporous crystalline material, with a characteristic X-ray diffractogram, comprised of oxygen tetrahedra and a metal (T<+4> and T<+3>) with the possibility of introducing surface acidity produced by the substitution in the lattice of some T<+4> cations by T<+3> cations, which gives rise to a structural charge deficiency that may be compensated by protons, Br¦nsted acidity, and/or high ratio radium charge cations, Lewis acidity. The obtention method is based on the preparation of a gel, its hydrothermal treatment under controlled conditions and the treatment of the resulting laminar material with a solution of an organic compound, preferably a long chain hydrocarbon, that contains a proton acceptor group. This swollen material is subjected to a specific treatment for the formation of interlaminar pillars of polymeric oxides, obtaining a pillared material that maintains the separation between the sheets, even after calcination.

Description

Acid oxide that has micro and Mesoporous: ITQ-36.

Technical field

The present invention relates to the area of the chemistry, in particular to materials of catalytic interest.

Background

The present invention concerns a mixed oxide provided with pillars that maintains a separation between the sheets, having individual structural layers, which has channels and microporous cavities

Laminar materials such as clays, phosphates, hydroxycarbonates, silicic acids (kanemite, magadiite, keniaite, etc.), transition metal sulfides, graphite, laminar and other hydroxides are capable of swelling in the presence of water and / or suitable interlaminar cations. The sheets Individuals of these materials are held together by means of weak forces of the type of hydrogen bonds and / or of electrostatic interactions These links break easily when the interleaving force or the solvation energy of the cations are greater than the forces of attraction interlaminar.

The interest of swollen materials is that make interlaminar space accessible to reactive molecules and, consequently, the internal surface, increasing considerably the active surface accessible to the reagent. When The intercalated material between the mixed oxide sheets is removed by calcination, the swollen laminar compound collapses, recovering the original interlaminar distance.

To prevent interlaminar collapse, it has been proposed the interleaving of "pillars" composed of thermally stable inorganic oxyhydroxides in the material swollen. These "pillars" are composed of hydroxides Polymers of Al, Si, Cr, Ni, Zr, etc ..., which after calcination treatment give rise to oxide columns corresponding that are anchored on the surface of the sheets, keeping them separate and stabilizing the product "propped up" final.

Objects of the invention

It is an object of the present invention provide a "propped up" material consisting of an oxide mixed, which maintains a separation between the sheets, having layers individual structural, which has channels and cavities microporous and that can be used as a catalyst in acid catalyzed reactions.

It is a further object of the present invention a method for preparing the sheet solid and subsequent treatment of the same, until obtaining a material with microporous pillars, highly accessible, with acidic characteristics capable of being Used as catalyst.

It is a further object of the invention the use of microporous material with pillars in reactions acid catalyzed such as cracking and isomerization of organic compounds, and preferably hydrocarbons, as well as in hydroisomerization and hydrocracking processes.

It is a further object of the invention to provide catalytic compounds containing the micro or mesoporous material with pillars and a matrix, and its use in processes of dewaxing and isodewaxing.

Finally, it is an additional object of the invention catalytic compositions comprising the micro material or mesoporous with pillars and a hydrogenating function.

Description of the invention

The present invention relates to an oxide that it is a material with pillars, as defined in claim 1, called ITQ-36, with a micro structure and mesoporous and an important external surface area, capable of support acidic centers of Brönsted and Lewis and characterized by its X-ray diffractogram and for its adsorption and its properties catalytic

ITQ-36 material has a chemical composition represented by the formula

(XO 2) n (Y 2 O 3) m (H 2 O) p

in which X represents at least a tetravalent element selected from silicon, titanium and Germanium and Y represents at least one trivalent element selected from aluminum, iron, boron, chrome and gallium, being the atomic relationship between X and Y of at least 5. In the embodiments preferred, the atomic ratio between X and Y is greater than 10, or even greater than 30. In a more preferred embodiment, said Atomic ratio is greater than 30, or even greater than 40. Limits suitable of said atomic ratio may be between 30 and 500

ITQ-36 material has a X-ray diffraction diagram with baseline distances and relative intensities summarized in Table 1.

TABLE 1

d (\ ring {A}) I / I_ {0} * 100 37.01 Mp 18.77 D 7.01 D 6.51 D 3.95 D 3.50 D 2.62 D 2.35 D

In this description, and unless specify otherwise, the relative intensities of the peaks of X-ray diffraction will be represented by the symbols and meanings presented hereinafter:

d weak 0-20% intensity relative m half 20-40% p powerful 40-60% mp very powerful 60-100%

The process of preparing oxide with pillars ITQ-36 consists of:

-

a first stage comprising the synthesis of a precursor that is a sheet material that can swell,

-

a second stage in which the sheet material obtained is swollen mixing it with a swelling solution, having as result a swollen laminar material that is a mixed laminar oxide swollen,

-

a third stage in which the swollen sheet material is washed and drying resulting in a swollen sheet material drying and

-

a fourth stage in which the swollen dried sheet material is "propped up", washed, dried and calcined to obtain the oxide mixed "propped up", ITQ-36, of the invention.

In the first stage, the synthesis is carried out of a solid that is a sheet material, mixing in an autoclave a source of at least one tetravalent element selected from between silicon, titanium and germanium, a source of at least one trivalent element selected from aluminum, iron, boron, chromium and gallium, a fluoride salt and a fluoride acid such as by example ammonium fluoride and hydrogen fluoride; a compound organic such as 1,4-diaminobutane, ethylenediamine, 1,4-dimethylpiperazine, 1,4-diaminocyclohexane, hexamethyleneimine and pyrrolidine, preferably, 4-amino-2,2,6,6-tetramethylpiperidine; and water in adequate proportions. The source of the element tetravalent in the case of silicon can be, for example, a silica source such as AEROSIL, LUDOX, CABOSIL, tetraethylorthosilicate (TEOS) or any other known; a fountain of a trivalent element; the source of the trivalent element in the Aluminum case can be a selected source from boehmite, pseudoboehmite, Al 2 (SO 4) 3, AlCl_3, Al (NO_ {3}) or any other.

The synthesis of said solid material takes place at temperatures between 100 and 200C with permanent agitation of the gel and lasting between 1 and 30 days and, preferably, between 1 and 18 days, and more preferably between 2 and 12 days. After this time, the reaction product, a white solid with a pH between 9 and 10, it is washed with distilled water, filtered and dried.

       \ newpage
    

During the second stage the swelling of the solid material obtained by preparing a suspension of it in a solution that we will call a solution of "swelling", formed by an organic chain compound long hydrocarbon having a proton acceptor group, such such as a quaternary alkylammonium, an amine or an alcohol with more than three carbons in the chain, to which an amount is added controlled of a compound capable of providing OH - to the medium reaction, such as an alkylammonium hydroxide quaternary, until a pH greater than 10 is obtained. The organic compound used as a source of OH - can be any amine or any quaternary alkylammonium compound, preferably cetyltrimethylammonium hydroxide (CTMA + OH -).

The prepared "swelling" solution is mixed with the solid material of the first stage previously described, in a proportion by weight of swelling solution with respect to solid sheet material between 4 and 200. The suspension resulting is kept under reflux and permanent agitation between 20 and 200 ° C, and preferably between 40 and 120 ° C, for a time not less than 1 hour until the swollen laminate is obtained.

During the third stage, the sheet material swollen is thoroughly washed with distilled water and dried to temperatures below 300 ° C, and preferably below 150 ° C In this way a dried sheet material is obtained swollen.

Once washed and dried, the dried material swollen has a characteristic x-ray diffraction diagram whose basal distances and relative intensities are summarized in Table 2

TABLE 2

d (\ ring {A}) I / I_ {0} * 100 28.20 Mp 14.45 P 9.81 D 6.46 D 4.31 M 4.10 M 3.93 M 3.65 D 3.49 M 2.87 D 2.62 D

Subsequently the process of "shoring" during the fourth stage. To this end, it prepares a suspension of the swollen dried material in an agent of "shoring", preferably tetraethylorthosilicate (TEOS), in a variable weight ratio between 2 and 20. This suspension it is kept under reflux and constant stirring at a temperature between 30 and 150 ° C, and preferably between 50 and 80 ° C, during a time not less than 1 hour and with permanent nitrogen flow until obtaining the "propped up" material.

During the fourth stage, the material "propped up" obtained is washed and dried at temperatures below 300 ° C. Once dry, it is calcined at temperatures between 300 and 800 ° C and, preferably between 400 and 600 ° C, giving rise to ITQ-36 product.

Shoring agents include polymeric oxides of elements of the VAT group of the Periodic Table of the elements, such as silicon, germanium or tin, or of the group IVB such as titanium, zirconium, etc., although they are normally chosen pillars that include polymeric silica. The oxides of "shoring" could also include an element that provide catalytically active acid sites on the pillars, preferably aluminum, gallium, a rare earth or mixtures of the same.

The ITQ-36 has, along with its laminar nature and its x-ray diffractogram, some characteristic texture properties as a result of having a microporous part, and an important area of the external surface as a result of the cavities formed by the interleaving of pillars between the plates. Thus, Table 3 summarizes the values obtained for a sample of ITQ-36 by applying the BET equation to the adsorption isotherm of nitrogen at the temperature of liquid nitrogen.

TABLE 3

S_ {TOT} (m2 / g) S_ {MIC} (m 2 / g) S_ {EXT} (m2 / g) V_ {TOT} (cm3 / g) V MIC (cm 3 / g) ITQ-36 716 68 648 0.7094 0.2734  \ begin {minipage} [t] {134mm} S_ {EXT} \ text {:} specific external surface, S_ {MIC} \ text {:} surface of the micropores, S_ {TOT} \ text {:} total area, V_ {TOT} \ text {:} total volume and V_ {MIC} means volume of micropores \ end {minipage}

ITQ-36 material can experience a later stage of hydrothermal calcination or a post-calcination in the presence of fluoride or a fluorine compound, or a treatment with a compound of match.

This ITQ-36 material is capable of be used as a catalyst in acid catalysis reactions such as cracking and isomerization of organic compounds, and preferably of hydrocarbons, as well as in hydroisomerization and hydrocracking, for which it is introduced along with the function acidic a hydrogenating-dehydrogenating function such such as platinum, palladium, nickel, rhodium, ruthenium or mixtures thereof.

The invention also relates to a composition. catalytic comprising an oxide material such as ITQ-36 and a hydrogenating function such as Pt, Pd, Ru, Ni, Co, Mo, V, W, Rh or any combination thereof, already are deposited in the rust material or on a surface support large such as alumina, silica or silica-alumina.

The invention further relates to the use of a catalytic composition, as defined in the paragraph above, in a process of isodeparaffinization of paraffins that comprises the contacting of the added hydrocarbon together with hydrogen at temperatures between 250 and 400 ° C, at pressures between 10 and 90 atmospheres, with the catalytic composition, as well as the use of said catalytic composition as a catalyst for dewaxing

The invention further relates to a catalytic compound formed by an oxide material like ITQ-36 and a matrix, which can be an oxide refractory.

The invention also relates to the use of said catalytic compound in a process for isomerization catalytic n-butenes in isobutenes, which implies contacting the hydrocarbon with the catalytic compound a temperatures between 300 and 500 ° C, as well as the use of said catalytic compound in a hydrocarbon cracking process that comprises bringing the hydrocarbons into contact with said catalytic compound at temperatures above 400 ° C, and which can be or not in the presence of steam.

Brief description of the figures

Figure 1 represents the diffraction diagram X-ray characteristic of swollen dried material and Figure 2 represents an ITQ-36 diffractogram.

Examples Example 1 (i) Preparation of swollen laminar mixed oxide

This example describes the preparation of an oxide mixed laminar with a Si / Al molar ratio, in the starting gel, of 5. Laminar oxide was prepared by mixing in an autoclave 10 grams of SiO2 (Aerosil 200, Degussa), 2.3 grams of Al_ {2} O_ {3} (Boehmite, Catapal B, Vista Corp., with 73.7% of Al 2 O 3), 9.2 grams of ammonium fluoride (NH 4 F, Aldrich, 98% pure), 3.1 grams of hydrofluoric acid (HF, Aldrich, at a concentration of 49.8%), 26 grams of 4-amino-2,2,6,6-tetramethylpiperidine (Fluka, 98% pure) and 27.9 grams of deionized water in MiliQ The synthesis gel, with a pH between 8 and 9, was maintained with vigorous stirring for one hour at room temperature. The resulting mixture was introduced in an autoclave and kept at 175 ° C for five days, after which the resulting product it was filtered and washed with 3 liters of deionized water to a pH ≤ 9, subsequently drying it in an oven at 60 ° C.

One gram (1 g) of the sheet material obtained is exchanged with a solution prepared with 20 grams of CTMA + OH - (29% solution), 6 grams of hydroxide tetrapropylammonium (TPA + OH -, 40% solution) and 4 grams of deionized water. The solution obtained is maintained, under reflux and vigorous stirring, for 16 hours at 95 ° C. Finally the suspension is thoroughly washed with water before the phase liquid is separated from the solid obtained. The swollen material (1.8 grams) has the diffraction diagram summarized in Table 2.

(ii) Preparation of the propped sheet material described in the invention

A suspension consisting of 1.5 g of the swollen sheet material together with 3 g of tetraethylorthosilicate, TEOS (Merck). This mixture is treated under reflux with stirring. constant at a temperature of 60 ° C for 16 hours, always under an atmosphere of inert nitrogen. Subsequently the solid is recovered by centrifugation (12000 rpm for 25 minutes). The material obtained is dried at 60 ° C overnight and is finally calcined at 580 ° C for 7 hours in the presence of air, to produce a material, in accordance with the present invention (1 gram), with a diffraction diagram similar to that of Figure 2, with the relative intensities summarized in Table 1.

Example 2

The process followed in Example 1 was repeated, except for the fact that the amounts of the reagents of Step (i) in order to obtain a gel with a Si / Al molar ratio of 30.

The oxide obtained at the end of Stage (ii) has a diffraction diagram similar to that of Figure 2 and intensities similar to those in Table 1.

Example 3

The process followed in Example 1 was repeated, except that in Stage (ii) a compound suspension was formed per 1.5 g of the swollen material and 15 g of tetraethylorthosilicate (TEOS), keeping the mixture under reflux for 24 hours at 80 ° C With an atmosphere of nitrogen. Once calcined, a product that had a diffraction diagram similar to the one in Figure 2.

Example 4

The process followed in Example 1 was repeated. except for the fact that in Stage (i) it was used N, N-tetradecylammonium (29% solution) instead of cetyltrimethylammonium hydroxide (CTMA + OH -). The swollen material that has a diffractogram similar to that in Figure 1 and relative intensities comparable to those in Table 2.

Example 5 Catalytic Experiments

0.05% by weight of platinum was added per impregnation with PtCl_6 to a sample of ITQ-36 with a Si / Al ratio of 30. The final material, after being calcined at 500 ° C for 3 hours, it was reduced in a reactor of fixed bed passing H 2 (300 ml 1 -1), the molar ratio H 2 / n-hexadecane of 50. The reaction conditions were: 40 atmospheres of total pressure and reaction temperatures between 290 ° C and 350 ° C. The results obtained, which are presented in Table 4, show that the ITQ-36 based catalyst is suitable for carrying out the dewaxing of hydrocarbons.

TABLE 4

Temperature % % % % Monkey- % Gave- % Tri- ºC Conversion Isomerization Cracking branched branched branched 294 20.72 2.67 18.05 2.67 0.19 0 310 72.53 3.51 69.02 3.51 0 0 322 88.91 3.26 85.65 3.26 0.67 0.07 335 96.64 2.36 94.29 2.36 0.67 0-17

Claims (37)

1. A propped laminar oxide material interspersed with pillars of at least one polymeric oxide, consisting said oxide material of at least one tetravalent element and at least a trivalent element of the Periodic Table and with a composition chemistry represented by the formula (XO 2) n (Y 2 O 3) m (H 2 O) p in which X represents one or more tetravalent elements selected from silicon, germanium and titanium and Y represents one or more selected trivalent elements between aluminum, boron, iron, boron, chrome and gallium, being the atomic relationship between X and Y of at least 5, and that has, in its form calcined, an X-ray diffractogram with basal distances and corresponding relative intensities to: d (\ ring {A}) I / I_ {0} * 100 37.01 60-100% 18.77 0-20% 7.01 0-20% 6.51 0-20% 3.95 0-20% 3.50 0-20% 2.62 0-20% 2.35 0-20% 2. An oxide material, according to the claim 1, which has in its calcined form characteristics of surface as follows: S_ {TOT} 716 m2 / g S_ MIC 68 m 2 / g S_ {EXT} 648 m2 / g V_TOT 0.7094 cm3 / g and V MIC 0.2734 cm 3 / g. 3. An oxide material, according to the claim 1, wherein the atomic ratio of X to Y is greater than 10 4. An oxide material, according to the claim 1, wherein the atomic ratio of X to Y is over 30. 5. An oxide material, according to the claim 1, wherein the atomic ratio of X to Y is over 40. 6. An oxide material, according to the claim 1, wherein the atomic ratio of X to Y It is in the range of between 30 and 500. 7. An oxide material, according to any of claims 1, 3, 4, 5 or 6, wherein X represents silicon. 8. An oxide material, according to any of claims 1, 3, 4, 5 or 6, wherein Y represents aluminum. 9. An oxide material, according to any of claims 1, 3, 4, 5 or 6, wherein X represents Silicon and Y represents aluminum. 10. A process for the preparation of a material oxide, as defined in any of the claims precedents, and that includes,

-

a first stage in which a laminar precursor is prepared capable of being swollen, mixing a source of at least one tetravalent element selected from silicon, titanium and germanium, a source of al minus a trivalent element selected from aluminum, boron, iron, chromium and gallium, a fluoride salt and a fluoride acid, a organic compound selected from 1,4-diaminobutane, ethylenediamine, 1,4-dimethylpiperazine, 1,4-diaminocyclohexane, hexamethyleneimine, pyrrolidine and 4-amino-2,2,6,6-tetramethylpiperidine; and water, in an autoclave, the mixture being continuously stirred at temperatures between 100ºC and 200ºC during a period between 1 and 30 days, until obtaining a solid that is washed and dried at a temperature below 300 ° C and which is capable of being swollen,

-

a second stage in which the solid capable of being swollen is mixed with a "swelling" solution in a weight ratio of swelling solution with respect to the precursor sheet material of between 4 and 200, the resulting suspension being kept low reflux and permanent agitation between 20 and 200 ° C for a period of time less than 1 hour, where the swelling solution has a pH greater than 10 and comprises an organic chain compound long hydrocarbon with a proton acceptor group and a group OH - donor, obtaining a sheet material swollen,

-

a third stage in which the swollen sheet material is washed thoroughly and dried resulting in a dried sheet material swollen that has an x-ray diffraction diagram characteristic with basal distances and relative intensities corresponding to:

d (\ ring {A}) I / I_ {0} * 100 28.20 60-100% 14.45 40-60% 9.81 0-20% 6.46 0-20% 4.31 20-40% 4.10 20-40% 3.93 20-40% 3.65 0-20% 3.49 20-40% M 2.87 0-20% 2.62 0-20%

Y

-

a fourth stage in which the swollen dried sheet material is propped up by means of shoring agents, using a suspension of the dried material swollen in an agent of shoring with a weight ratio between 2 and 20, keeping said suspension under reflux and nitrogen flow for at least one hour, washing the propped up material obtained, drying it and calcining it, to obtain the mixed oxide provided with pillars ITQ-36

11. A process according to claim 10, in which the source of the tetravalent element is a source of silicon and the source of the trivalent element is a source of aluminum. 12. A process according to claim 11, in which the source of silicon is a source of silica selected from AEROSIL, LUDOX, CABOSIL and tetraethylorthosilicate (TEOS). 13. A process according to claim 11, in which the aluminum source is selected from boehmite, pseudoboehmite, Al 2 (SO 4) 3, AlCl 3 and Al (NO_ {3}). 14. A process according to claim 10, in which the sources of fluoride salt and fluoride acid are ammonium fluoride and hydrogen fluoride, respectively. 15. A process according to claim 10, in which the organic compound of the first stage is 4-amino-2,2,6,6-tetramethyl-piperidine. 16. A process according to claim 10, in which the first stage is carried out during a period of between 2 and 12 days at an autogenous pressure in an autoclave. 17. A process according to claim 10, in which the solid obtained in the first stage has a pH of between 9 and 10. 18. A process according to claim 10, in which the solid obtained in the first stage is dried at a temperature below 200 ° C. 19. A process according to claim 10, in which the organic compound of the swelling solution is selected from a quaternary alkylammonium, an amine and a alcohol with more than three carbons in the chain. 20. A process according to claim 10, wherein the source of OH - groups in the solution of swelling is cetyltrimethylammonium hydroxide. 21. A process according to claim 10, in which in the second stage the solid material capable of being swelling is maintained in the swelling solution at a temperature between 40ºC and 120ºC. 22. A process according to claim 10, in which the swollen sheet material is dried to a temperature below 150 ° C. 23. A process according to claim 10, in which the shoring agents are polymeric oxides of items selected from VAT group items and items from group IVB of the Periodic Table. 24. A process according to claim 10, in which the shoring agents also contain elements that provide catalytically active acid sites in the pillars. 25. A process according to claim 24, in which the elements that provide acid sites catalytically active in the pillars are selected from aluminum, gallium, rare earths and mixtures thereof. 26. A process according to claim 10 or 23, in which the shoring agent is tetraethylorthosilicate. 27. A process according to claim 10, in which in the fourth stage the propped sheet material is calcined at temperatures between 300 and 800 ° C. 28. A process according to claim 10, in which the ITQ-36 material experiences a later stage of hydrothermal calcination. 29. A process according to claim 10, in which the ITQ-36 material experiences a post-calcination in the presence of fluoride or a fluorine compound 30. A process according to claim 10, in which the ITQ-36 material experiences a Treatment with a phosphorus compound. 31. A catalytic composition comprising a oxide material according to any one of claims 1 to 9 and a hydrogenating function such as Pt, Pd, Ru, Ni, Co, Mo, V, W, Rh or any combination thereof, already deposited in the oxide material or on a large surface support such as alumina, silica or silica-alumina. 32. The use of a catalytic composition according to claim 31 in a process for the paraffin isodeparaffination comprising contacting of the hydrocarbon added together with hydrogen at temperatures between 250 and 400 ° C, at pressures between 10 and 90 atmospheres, with the catalytic composition 33. The use of a catalytic composition according to claim 31 as catalyst of dewaxing 34. A catalytic compound formed by a oxide material according to any one of claims 1 to 9 and a matrix. 35. A catalytic compound, according to the claim 34, wherein the matrix is a refractory oxide. 36. Use of a catalytic compound of according to claim 34 or 35 in a process for catalytic isomerization of n-butenes in isobutenes, which involves bringing the hydrocarbon into contact with the compound catalytic at temperatures between 300 and 500 ° C. 37. Use of a catalytic compound of according to claim 34 or 35 in a cracking process of hydrocarbons comprising the contacting of hydrocarbons with the catalytic compound at higher temperatures at 400 ° C, and that may or may not be in the presence of steam.